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Merlin

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  1. Bear in mind that if, at some point, you do a PST mod. it’s absolutely essential to have a D-ERF ( Energy Rejection Filter ) over the front of the donor ‘scope. Please don’t attempt a PST mod until you have all of the information you need. I modded a 70mm refractor and it gives good results.
  2. You won’t go wrong with Opticron. I have a pair of 8X40’s, very good.
  3. We can hold X20 binoculars quite steadily if we mount them on a triangular frame with handgrips on the bottom. I made a frame from aluminium tubing and it works well with the 25X70 bins.
  4. I once witnessed a solar flare. It became intense white then faded, all in a few minutes.
  5. The minimum magnification that can usefully be used on a ‘scope is about four times the aperture in inches. That’s X20 with your five-incher
  6. It’s better if contributors to the thread say what kind of ‘scope they are using. Only one contributor has done this. Thanks. Stating the instruments used assists beginners and upgraders to know what to expect from a particular solar ‘scope.
  7. There’s an easy solution to making a dovetail bar safe and that’s to file a slot on one side, so that the locking screw is secured in the slot.
  8. It’s better if contributors to the thread say what kind of ‘scope they are using. Only one contributor has done this.
  9. The Russians are planning to build rockets capable of lifting 200 tonne payloads. So, there could be some impressive space telescopes launched in coming years.
  10. Consider, too, a good spotting ‘scope. I have an Acuter 80mm diameter one with a zoom eyepiece. Being a spotter, it’s a general purpose ‘scope.
  11. An good eight-inch reflector is a great ‘scope. Not too big and not too small to handle. It gives splendid views of many objects.
  12. Back in the 1950s, I bought a long focus lens of about 50-inches from the H.W.English catalogue, which was a veritable Alladin’s cave of government surplus items. My interest in astronomy was fired by a little astronomy book in the school library, with the enchanting title “ The Star-Spangled Sky”, authored by a vicar. The “ objective” lens was about three-and-a- half inches in diameter. It was very thin like a big convex/concave spectacle lens. My dad, who had no interest in astronomy, made me a main tube ( no glare stops ) with a simple push-pull inner tube, a simple AltAz mounting and a tripod- all in cold steel at the local engineering firm where he worked. The eyepiece, also acquired from the English catalogue, was a flawless big brass gunsight eyepiece, which I reckon yielded a magnification of about 50X. Aged twelve, on a warm summer evening while it was still light, I pointed the crude ‘scope at a gibbous moon. It was a revelation. I was astounded to see the lunar craters and mountains for the first time. This was followed by an overpowering feeling that I could travel anywhere in the Universe with my newly-acquired refractor. Surprisingly, I didn’t notice any chromatism from the non-achromatic “objective”. This crude instrument inspired two friends to take up astronomy as a hobby. One made a four-inch reflector and the other a eight-inch reflector ( followed by a fifteen-inch reflector, but which was never completed due to him emigrating ).All the ‘scopes were fitted with bought out optics. Since then, I’ve never lost interest in our beautiful hobby.. .
  13. I had a Prinz 3-inch/f.16 refractor on an equatorial mount in the 1970s. It was a good ‘scope and brand new from Dixon’s. I remember that both the ‘scope and its wooden box had a pleasant odour.
  14. A traditional way to remove dew from an objective is to place a warm, absorbent, cloth inside the dew shield then cap it.
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